Estimated prevalence of Johne's disease in herds of water buffaloes (Bubalus bubalis) in the province of Caserta

Paratuberculosis is a chronic infection of domestic and wild ruminants, caused by Mycobacterium avium subsp. paratuberculosis. The persistence of paratuberculosis infection for months up to years without exhibiting any clinical signs makes the diagnosis and control program a difficult proposition. Limited informations on prevalence of paratuberculosis in water buffaloes (Bubalus bubalis) are available. We carried out a study on 1350 buffaloes belonging to 56 herds in the Caserta province, of Campania region, Italy. The prevalence of infected buffalo dairy herds was estimated by a commercial ELISA kit of individual blood samples of animals over 24 months of age. On the basis of performance (sensitivity 43%, specificity 99.3%) of ELISA test on serum, the resulting true prevalence at animal level and at herd level was 4% (95% CI 3% to 5%) and 74,1% (95% CI 71.8% to 76%). Considering the paucity of epidemiological reports in the region our results could be a useful contribution towards the prevention of buffalo paratuberculosis in the area.